Lips

The upper and lower lips make a frame around the teeth, gingiva, and the oral cavity to form the external border of a smile and the shape and mobility of the lips can influence the amount of tooth and gingival display. Research has established that individuals with different training weigh the relative value of lips and teeth on esthetics of a smile. Orthodontists rated teeth and lips equally in relation to smile esthetics, whereas restorative specialists are more influenced by the lips than the teeth.²⁴ In contrast, laypersons failed to identify the esthetic details and component of the smile.²⁴